Heat-treating furnace



March 27, 1945.

A. N. 0115 ETAL HEAT TREATING FURNACE Filed March 19, .1943

Inventors: Albert N. Otis;

George W He el, by Fa/11175.3

Thai T Attorney.

Patentcd Mar. 27, 1945 1 OFFICE HEAT-TREATING FURNACE Albert N. Otis, Schenectady, and George W.Hegel, Scotia, N. Y., assignors to General Electric Com-' pany, a corporation of New York Application March 19, 1943, Serial No. 479,752

3 Claims.

Our invention relates to heat treating furnaces of the type in which objects to be treated are passed continuously through the furnace. The object of our invention is the provision of such a furnace having improved means by which objects of a cylindrical form are passed in succession through the furnace.

Our invention will be better understood from the following description taken in connection with the accompanying drawing, and its scope will be pointed out in the appended claims.

Referring to the drawing, Fig. 1 is a side view partly in section of a portion of a furnace embodying our invention; Fig. 2 is a detail perspective view of a smaller portion thereof drawn to a larger scale; and Fig. 3 is a further detail drawn. to a still large scale.

The furnace l which in part may be of well known construction has a heating chamber 2, the entrance opening 3 and the door 4 for closing that opening, the chamber being heated by any suitable means such as an electrical heater, not

shown. On the bottom of the furnace is the track 5 which extends through the furnace entrance, through the furnace chmaber, and on through the exit thereof, not shown, terminating,

for example, over a quench tank, also not shown. Opposite the entrance end of the track is the pusher 8 by which the objects to be heat treated are moved into and through the furnace. As illustrated more clearly in Fig. 2 the track comprises the rails l, t, 9 and it which support objects to be heat treated having a cylindrical form and upon which they are arranged to roll. Such objects are illustrated by way of example as the I shells i l which are pointed at one end and are flanged at the other. In addition to the abovementioned rails we have shown at i? an auxiliary or safety rail which in the event of an accidental displacement of an object in the direction of that rail will by engaging the pointed end of the object prevent the object from tipping off the track. Overlapping the flanged ends or the'objects we have shown the guide rail it. The track also comprises other supporting rails 05 and is.

As the objects roll through the furnace on the rails l-lli inclusive it is desirable that they be maintained spaced apart a suitable distance. The track while horizontal may be slightly inclined downward toward the rear of'the furnace so that 'little or no eilort'is required to push the objects along. For so pushing them or controlling their movement without any tendency to cause them to become skewed on the track we have provided a numberof separate shoes it which by engaging each other are pushed through the furnace in the former a train. Each shoe comprises the two runners 20 and 2| whose length is equal to the distance between the centers of the objects I l. The runners are arranged to be supported by and slide on the rails l5 and I6 respectively, the ends of the runners being upwardly inclined. The two runners of a shoe are rigidly connected. together by the transverse plate 22 having the side flanges 23 which plate extends over and across the rails upon which the objects roll. As the shoes are pushed along the track each plate engages the cylindical surface of the object next ahead of it or behind it, the width of the plates being such as to provide the desired spacing between the objects. As a safe-guard against a possible tipping up of the right hand ends of the shoes as viewed in Fig. 2, the runners 29 are provided with the cleats 26 which extend beneath the head 25 on the rail i161 The pusher ti, which may be hydraulically 0perated, is shown having the plunger 2i engaging the transverse bar 23 which is constructed or is provided with suitable means, not shown, to maintain it at right angles to the track. Projecting from the bar 28 are the two spaced pusher rods 29 each of Which alines with one of the runners 2t, 2 l.

In the operation of the furnace, objects M. to be heat treated are laid one at a time on the rails t5 and it in front of the furnace door. When it is desired to move another object into the furnace the furnace door is raised and the pusher is operated which by pushing against the last added shoe pushes the object in front of it through the entrance into the furnace chamber: In so doing the shoe engaged by the pusher pushes the whole train ofshoes already in the furnace causing each object to roll along to a new position and causing the last object and shoe ahead of it to be expelled from the exit end of the furnace. The expelled object may fall into or be removed and placed in a quench tank. and the preceding shoe presumably will be returned to the entrance end of the furnace to be ready for use again.

During the operation of the pusher each shoe of the train engages and pushes along the shoe next ahead of it and each shoe functions to maintain the two objects adjacent thereto in spaced relation with each other. Depending upon the degree of slope of the track if such there be each shoe will either push along the object next ahead at all times perpendicular to the track the two pusher rods 29 push equally against the two runners of a shoe. Not only, therefore, is that shoe which is directly engaged by the pusher moved into the furnace in a perpendicular relation with the track but all the shoes ahead of it will be moved in the same manner whereby there is no danger of any of the shoes or the objects moved thereby becoming skewed in the furnace.

What we claim as new and desire to secure by Letters Patent of the United States, is:

1. In a heat treating furnace, a track extending through the furnace chamber comprising rails upon which objects to be treated having cylindrical surfaces are adapted to roll 'and other rails, a plurality of shoes having contiguous runners mounted to slide on said other rails and having transverse plates connecting said runners in pairs and extending over said first mentioned rails, said plates being adapted to engage substantially throughout their length the cylindrical surfaces of'said objects and to space said objects.

2. A heat treating furnace comprising walls forming a furnace chamber having openings at opposite ends, a plurality of rails extending through said chamber in spaced parallel relation with each other forming supports on which cylindrical objects to be heated are rolled through the chamber, and means for maintaining the cylindrical objects in spaced relation with each other e comprising a plurality of spacing members extending transversely across said rails, two downwardly extending runner'members on opposite of said rails greater than the width of said spacing member whereby the ends of adjacent runner members engage each other so as to hold said spacing members spaced apart a distance greater than required by a cylindrical object between them, supporting rails on which said runners move so as to support said spacing members.

3. A heat treating furnace comprising walls forming a furnace chamber having openings at opposite ends, a plurality of rails extending through said chamber in spaced parallel relation with each other forming supports on which cylindrical objects to be heated are rolled through the chamber, and means for maintaining the cylindrical objects in spaced relation with each other comprising a plurality of spacing members extending transversely across said rails, two downwardly extending runnennrgibers on opposite ends of each of said spacing members, each of said runner members having a length lengthwise of said rails greater than the width of said spacing member whereby the ends of adjacent runner members engage each other so as to hold said spacing members spaced apart a distance slightly greater than required by a cylindrical object between said spacing members, supporting rails on which said runners slide so as to support said spacing members, at least one of said supporting rails being provided with a flange extending lengthwise thereof, and an interlocking projection on the adjacent runner member extending under said flange thereby to secure said runner member against upward movement.

ALBERT N. OTIS.

GEORGE W. I'IEGEL. 

